wnol.info May 30 2017


Scientists unveil facts about bite of T. rex

May 30 2017, 07:25 | Guillermo Bowen

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Tyrannosaurus rex jaws generated 8,000-pound bite forces and let the creature eat everything from duck-billed dinosaurs to triceratops

Yet it was far from your average dinosaur.

Modern day bone crushers include both the wolf and the hyena, however both are unlike T. rex in that they are of course mammals. Francois Therrien works at the Royal Tyrrell Museum of Palaeontology in Canada. Researchers compared the teeth of the T. rex to high heels. The study authors said their report was the first to examine the pressure exerted by dino dentition.

They concluded T. rex possessed the greatest tooth pressure of any creature ever studied. It was enough to cause the toughest dinosaur bones to fracture.

Indeed, having high bite force doesn't necessarily mean an animal can puncture or pulverise bone - for this studying tooth pressure is more relevant. Bone marrow is rich in fat and calories. Their teeth aren't created to.

The original skull of a Tyrannosaurus rex skeleton is shown at the Natural History Museum in Berlin, Dec. 16, 2015. You might remember those imposing teeth.

Wolves and hyenas, for example, are also able to crush bones with their teeth, accessing nutritious marrow.

Bite marks on fossilised bones of dinosaurs like the horned Triceratops that lived alongside the T-rex some 66 million years ago in western North America indicated that it was a bone-cruncher. "That's like setting three small cars on top of the jaws of a T. rex - that's basically what was pushing down".

Erickson and Gignac derived their conclusions from testing and modeling how the musculature of crocodilians, close relatives of dinosaurs, contribute to bite forces.

But the real damage T. rex inflicted came from its teeth, each of which could exert pressures reaching 431,000 pounds per square inch (2,974 megapascals), "which allowed T. rex to bite through and even shatter bone before consuming it", said lead study researcher Paul Gignac, an assistant professor of anatomy and vertebrate paleontology at the Oklahoma State University Center for Health Sciences.

It's not the first time researchers have investigated the Tyrannosaur's bite force. A few older estimates reported jaws four times as powerful. Besides its enormous size and force, the Tyrannosaurus rex was helped by a specific set of tooth characteristics.

They reconstructed a 3D muscle architecture based on the crocodile's jaw, specifically the Alligator mississippiensis. It was a "great approach", he said, "and the values are probably reasonable". The specimen had a T. rex tooth in its tail, in a wound that had healed after the teeth had entered the bone. "It's that pressure that's going to go through hide or bone or not", stated Gregory Erickson. Furthermore, previous studies on fossilized T. rex stool, also known as coprolites, show that they also enjoyed highly acidic stomach fluids, which allowed them to digest whole carcasses just like crocodiles do.

The teeth also may have compensated for the dinosaur's puny arms when hunting.

"These dinosaurs were literally headhunters, because everything had to be done with the head", said paleontologist Fran├žois Therrien.

T-Rex probably cracked the bones of its prey open as easily as you might crack open the bones of a chicken - and it did it for much the same reason you might. In that case, a ferocious, bone-breaking bite goes a long way.



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